Well my Doors record is listenable now, but I wouldn't say it's a reference copy or restored. I'd say half the sizzling bacon is gone, but quiet passages are still not great. Maybe a second coating.
As for gluing two together, I don't think pulling them apart would be an issue. I would definitely put a pull tab of something between them. I would also experiment two records with larger run out sections. STaL maybe on to something with the raised edge.